The present invention relates to N-alkyl derivatives of antibiotic BU-3608 complex. These compounds are active as antifungal agents.
The fermentation, and isolation and purification procedures for antibiotics BU-3608, BU-3608 B, and BU-3608 C are described in detail in our co-pending application U.S. Ser. No. 115,273 filed Nov. 2, 1987 now U.S. Pat. No. 4,870,165; the isolation and purification procedures for antibiotics BU-3608 D and BU-3608 E are described in our co-pending application U.S. Ser. No. 203,776, filed June 7, 1988 now pending. These applications are hereby incorporated by reference. The structures of the above mentioned antibiotics are given below as formula Ia-Ie. ##STR1##
Ia: BU-3608; R.sup.1 =CH.sub.3 ; R.sup.2 =D-xylosyl; R.sup.3 =CH.sub.3
Ib: BU-3608 B; R.sup.1 =CH.sub.3 ; R.sup.2 =H; R.sup.3 =CH.sub.3
Ic: BU-3608 C; R.sup.1 =CH.sub.3 ; R.sup.2 =D-xylosyl; R.sup.3 =H
Id: BU-3608 D; R.sup.1 =H; R.sup.2 =D-xylosyl; R.sup.3 =CH.sub.3
Ie: BU-3608 E; R.sup.1 =H; R.sup.2 =D-xylosyl; R.sup.3 =H.
BU-3608, however, has very limited solubility in water. Thus an object of the present invention provides water soluble derivatives of the various components of the BU-3608 antibiotic complex.